He had decamped to the United States in March to try to “step up to the next
level” with new coach Alberto Salazar, but Mo Farah could not have dreamed
the improvement would come so quickly.

On what could well prove a watershed night for British male endurance running, the Somali-born Londoner produced the greatest performance of his life at the Prefontaine Classic in Eugene, Oregon, to smash the British and European 10,000 metres records.

Biding his time at the back of a truly world-class field before hitting the front with 2½ laps remaining, Farah blew away his opponents to cross the line in 26min 46.57sec — comfortably inside the previous 11-year-old European record of 26-52.30 held by Belgium’s Mohammed Mourhit and obliterating Jon Brown’s 1998 British mark of 27-18.14.

His time also took him to the top of this year’s world rankings, not to mention 14th on the world all-time list, and served notice that after his 5,000-10,000m double at last summer’s European Championships in Barcelona, he is now ready to challenge for silverware at world and Olympic level.

To put his performance into context, Farah was more than 14 seconds inside the Olympic record set by Ethiopia’s Kenenisa Bekele when he won the 10,000m gold medal in Beijing in 2008.

It was also vindication of his decision to move his family out to America three months ago to join Salazar’s 'Oregon Project’ in search of the extra seconds that would make him competitive at this summer’s World Championships in South Korea and, more importantly, in his home city next year.

The American coach is renowned for his attention to detail and his willingness to deploy innovative training methods. Farah’s new regime has included long sessions pounding away on an underwater treadmill to increase his strength while minimising the risk of injury.

Farah, 28, who lowered his 10,000m lifetime best by more than 42 seconds, has yet to lose a race since making the switch, having retained his European indoor 3,000m title and scored resounding victories in the New York Half Marathon and last week’s BUPA London 10,000.

Before the Eugene meeting, the fourth leg of the Diamond League series, Farah had declared his intention to challenge the British record.

But, having followed Salazar’s instructions to stay out of trouble and conserve his energy in the first half of the race, he turned his attention to the European mark in the final stages after hearing cries from the trackside that the record was within reach. He duly wound up the pace and covered the last kilometre in 2min 30.72sec.

“I just sat at the back and worked my way through the field,” he said. “I want to thank my coach, who has worked me really hard on the Oregon Project. It’s paid off.”

He added: “If it wasn’t for the crowd I would never have done this. With three laps to go I knew I had the chance for the record.”

Just as impressive as his winning time was the manner in which he outclassed a field loaded with East African talent, including Ethiopian Imane Merga, currently one of the best distance runners in the world and winner of last year’s overall Diamond League 5,000m title.

Like Farah, Merga produced a lifetime best but still finished two seconds behind the Briton, who also claimed the scalps of world silver medallist Zersenay Tadese, who was fifth, and Olympic silver medallist Sileshi Sihine, who was sixth.

Of the 20 athletes who finished the race, 14 set personal bests and nine went under the 27-minute barrier.

Having broken David Moorcroft’s 28-year-old 5,000m record last year, Farah can now claim to be the greatest male distance runner ever to run in a British vest, though he insists he will not be satisfied until he has won a medal on the global stage. That ambition now looks highly achievable.

Ian Stewart, who won the Olympic 5,000m bronze in 1972 and is now UK Athletics’ head of endurance, hailed Farah’s performance as a major breakthrough.

“That run from Mo was quite extraordinary and puts him firmly in the mix with the world’s best athletes,” he said. “This result absolutely shows that British distance runners can take on and beat the best in the world.”

Justin Gatlin finished sixth in a blistering 100 metres at the Diamond League meeting in Eugene tonight.

Gatlin, who is returning from a drugs ban, broke the 10 second barrier with a time of 9.97, but finished well adrift of Jamaica's Steve Mullings who won in a time of 9.80.

Six of the eight runners finished in under 10 seconds as the wind helped in Oregon.

The wind also helped Britain's Greg Rutherford to win the long jump in 8.32m, 2cm further than his record from the 2009 World Championships, but the conditions meant it will not stand as a British record.

South Africa's Caster Semenya made her Diamond League debut in the 800m, but could only manage second place behind Kenia Sinclair.

American Tyson Gay sent a message to Usain Bolt and his other 100m rivals by clocking a scorching 9.79sec at a low-key meeting in Clermont, Florida, to leap to top of the world rankings.

Jamaican sprinter Steve Mullings also threw down the gauntlet with a winning time of 9.80sec at the Prefontaine Classic. Bolt has managed just 9.91sec in his two 100m races so far this year.